CVE-2011-0915 in Lotus Domino
Summary
by MITRE
Stack-based buffer overflow in nrouter.exe in IBM Lotus Domino before 8.5.3 allows remote attackers to execute arbitrary code via a long name parameter in a Content-Type header in a malformed Notes calendar (aka iCalendar or iCal) meeting request, aka SPR KLYH87LL23.
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Analysis
by VulDB Data Team • 10/14/2021
The vulnerability identified as CVE-2011-0915 represents a critical stack-based buffer overflow in IBM Lotus Domino's nrouter.exe component, affecting versions prior to 8.5.3. This flaw exists within the handling of malformed Notes calendar meeting requests, specifically when processing the Content-Type header with an excessively long name parameter. The vulnerability operates through the iCalendar format commonly used for calendar data exchange, making it particularly dangerous as calendar applications are widely deployed and frequently accessed by users across various organizational networks.
The technical implementation of this vulnerability stems from insufficient input validation within the nrouter.exe process, which is responsible for routing and processing email and calendar data within the Lotus Domino environment. When a maliciously crafted calendar meeting request containing an overly long name parameter in the Content-Type header is processed, the application fails to properly bounds-check the input data before copying it into a fixed-size stack buffer. This buffer overflow condition allows attackers to overwrite adjacent memory locations, potentially corrupting the stack frame and enabling arbitrary code execution with the privileges of the nrouter.exe process, which typically runs with elevated system permissions.
The operational impact of this vulnerability extends beyond simple remote code execution, as it provides attackers with a pathway to compromise entire Domino servers and potentially gain access to sensitive organizational data. The attack vector requires only a single malformed calendar meeting request to be sent to a vulnerable server, making it particularly attractive to threat actors seeking to exploit this vulnerability at scale. Organizations using Lotus Domino for email and calendar services face significant risk, as calendar data is frequently exchanged between internal and external parties, increasing the attack surface for potential exploitation.
Mitigation strategies for CVE-2011-0915 should prioritize immediate patching of affected systems to IBM Lotus Domino version 8.5.3 or later, as this release contains the necessary fixes for the buffer overflow vulnerability. Network administrators should also implement additional protective measures including email filtering rules that can identify and block malformed calendar meeting requests, particularly those containing unusually long Content-Type headers. The vulnerability aligns with CWE-121 stack-based buffer overflow classification and represents a significant concern under the ATT&CK framework's execution and privilege escalation tactics, where adversaries can leverage such vulnerabilities to establish persistent access to target networks through remote code execution capabilities. Organizations should also consider implementing network segmentation and monitoring solutions to detect unusual calendar data traffic patterns that might indicate exploitation attempts against this vulnerability.